Epoxy ethers are an important starting material in the chemical industry. For instance, Heloxy® modifiers are epoxy functionalized alcohols, with originally one or more hydroxyl groups. These modifiers are offered for instance in the form of monofunctional glycidyl ethers, and polyfunctional glycidyl ethers. Modifiers help improve cured system flexibility, increase peel and impact strength, increase the level of filler loading, improve resin wetting action, and reduce viscosity and surface tension. In particular the polyfunctional glycidyl ethers are useful. Of similar relevance are the epoxidation products of vinyl ethers of alcohol, diols and polyols.
The glycidyl ethers may be prepared using epichlorohydrin and alcohols (diols and polyols). From an environmental perspective, finding an alternative route would be rather attractive. In the Journal of Molecular Catalysis A: Chemical 244 (2006) 173-178 by E. Kaczmarczyk et al “Epoxidation of 1,4-bis(allyloxy)butane by Hydrogen Peroxide Under Phase Transfer Catalysis” the preparation of the diglycidylether of 1,4-butanediol was investigated. Both a monoepoxide and a diepoxide were produced. Diallylether was epoxidized by Peng Wu et al, “A Novel Titanosilicate With MWW Structure Catalytic Properties In Selective Epoxidation Of Diallyl Ether With Hydrogen Peroxide” in Journal of Catalysis 228 (2004) 183-191.
In the Journal of Molecular Catalysis A: Chemical 235 (2005) 52-56 “Epoxidation of 1,4-Diallyloxybutane To 1-Allyloxy-4-Glycidyloxybutane By The Method Of Phase Transfer Catalysis” by E. Kaczmarczyk et al the epoxidation of 1,4-diallyloxybutane (DiAB) with 30 wt % hydrogen peroxide in the presence of phosphorotungstic acid (PTA) hydrate or phosphoric(V)-acid-sodium tungsten(VI) dihydrate system (PO43−/WO42−) as the catalysts and an (phosph)onium salt as a phase transfer catalyst was investigated. Again by E. Kaczmarczyk et al the epoxidation of 1,4-bis(allyloxy)butane was investigated in Journal of Molecular Catalysis A: Chemical 265 (2007) 148-152, “Selective Epoxidation Of 1,4-Bis(Allyloxy)Butane To 1-Allyloxy-Glycidoloxybutane In The Presence Of Ionic Liquids”.
The inventors set out to find an alternative route to glycidyl ethers that does not rely on epichlorohydrin. Such an alternative route has been found. Moreover, this new route also opens the possibility of preparing epoxyethyl ethers which will find use in the same applications where the glycidyl ethers are used. The present invention provides an attractive route to such products.